A totally implantable intrapleural artificial lung (AL) is presented. The AL is designed to fully support adult human patients who require long term (more than one month) artificial gas exchange support necessary for treatment and recovery. The device will also provide a bridge to lung transplantation when lung recovery is impossible. The AL is designed to be perfused entirely by the right ventricle while the device is placed in series or in parallel with the native lungs (i.e., pulmonary artery (PA) to PA, or PA to left atrium. MC3 has prototyped several extremely low resistance, highly efficient artificial lungs, and in collaboration with the University of Michigan, has successfully implanted ten devices in 5 to 8 hour acute sheep experiments. In these experiments the AL was capable of fully supporting adult sheep while the blood pressure drop across the device was tolerable by the right ventricle. Our objective in Phase I will be to further research this design and to fully characterize the hemodynamics and gas exchange of devices that are made from silicone membrane and coated microporous hollow fibers. This characterization will be helpful in determining how the various design parameters affect resistance to blood flow and gas exchange. Based on these results we will improve the design to advance our studies aimed at long term use. PROPOSED COMMERCIAL APPLICATION: The commercial potential for this device is extensive. The number of potential bridge to lung transplant candidates in the US is currently over 1,000 of which 50% are rejected because of scarcity of available donor lungs, infectious complications, and simply because they cannot tolerate the surgical procedure thereby making them too high of a risk for very precious organs. Additionally this device may be used in patients with end stage respiratory failure who are not suitable candidates for lung transplant and patients who undergo lung transplantation failure.